The present invention relates generally to the field of dispensers. In particular, the present invention is a definite length tape dispensing apparatus for dispensing thin adhesive tape.
Dispensers for dispensing pressure-sensitive adhesive tape are generally known. One such dispensing apparatus known as an M-82 Definite Length Dispenser is available from the Minnesota, Mining and Manufacturing Company of St. Paul Minn. The M-82 Definite Length Dispenser includes a feed mechanism, a drive assembly for driving the feed mechanism and a stripper mechanism driven by the drive assembly through the feed mechanism. The feed mechanism is defined by a plurality of circular feed discs that are adapted to unwind adhesive tape from a tape roll upon manual actuation of the drive assembly. The stripper mechanism is defined by a plurality of circular stripper discs (the number of stripper discs being equal to the number of feed discs) that are adapted to strip the adhesive tape from the feed discs so that a free end of the adhesive tape can be easily grasped by a user of the Definite Length Dispenser.
The prior art M-82 Definite Length Dispenser is capable of dispensing thick adhesive tape (i.e., adhesive tape having a backing material thickness of greater than 2 mils) or thin adhesive tape (i.e., adhesive tape having a backing material thickness of 2 mils or less). The inherent stiffness of the thick adhesive tape (due to the thickness of its backing material) normally allows the thick tape to come straight off of the stripper discs, such that the free end of the thick tape can be easily grasped by a user of the Definite Length Dispenser. Due to its inherent stiffness, the thick adhesive tape is able to overcome forces that may cause the tape to adhere to the stripper discs. These forces being (1) static present as result of the tape being unwound from the tape roll and (2) adhesive attraction due to the adhesive material on the tape.
Thin adhesive tape, on the other hand, due to the thinner nature of its backing material, does not have the inherent stiffness of thick adhesive tape. Hence, thin adhesive tape, when used with the M-82 Definite Length Dispenser, tends to simply ride with the stripper discs because the combination of (1) static and (2) the adhesive attraction of the adhesive material on the tape is greater than the combating force provided by the minimal inherent stiffness of the thin adhesive tape. Therefore, the thin adhesive tape, when used with the Definite Length Dispenser, typically does not come straight off of the stripper discs (as is the case with the thick adhesive tape) and as such the free end of the thin adhesive tape is not presented such that it can be easily grasped by the user of the Definite Length Dispenser. Typically, thin adhesive tape, when used with the Definite Length Dispenser must be peeled off of the stripper discs, thereby making the prior art M-82 Definite Length Dispenser difficult and frustrating to operate when used with thin adhesive tape.
Furthermore, it is preferable to rotate the stripper discs at a rotational speed faster than the rotational speed of the feed discs to facilitate the stripping of the adhesive tape from the feed discs. In this situation, if the adhesive tape adheres to the stripper discs, the machine will lock up. Thus, with adhesive tapes that tend to stick to the stripper discs, machine operation may be impossible.
There is a continuing need for improved tape dispensers. Specifically, there is a need for a definite length tape dispensing apparatus for dispensing thin adhesive tape such that a free end of the dispensed tape is presented such that it can be easily grasped by a user of the dispensing apparatus.